See the first, explanatory post in this thread. All cards start out as 'New' cards, meaning Anki doesn't expect you to know them, and therefore it does not apply its spaced repetition algorithm to them. In order to turn a New card into a Review card (where Anki gradually increases the interval between times you see the card, based on how well you know it), it has to go through a Learning phase. In order to complete the Learning phase and 'graduate' to Review card status, Anki will show you the card in a series of fixed intervals and you have to get it right every time or else start over. Those are your learning steps/intervals, and they can be changed in the New card settings (first tab in Deck options). Of note, how often you get the card wrong during Learning and then whether you ever mark it Easy will affect how quickly your intervals grow once it becomes a Review card. For more details, check out the Anki manual or else the first post in this thread.
I recommend setting the Learn steps such that, if you miss the card, you see it again right away (1), if you get it right, you won't see it again during that review session, but you'll see it again if you do another review session later that day. That allows me to do a morning review session, where I go through all Due cards and all New cards until I get them right, and then another session whenever I have time later that day where I do all of the cards I just started Learning that morning and as many New cards as I have time for. If I get them right in the evening, those cards will all graduate into Review cards. If not, I'll see the card over again until I get it right, and then try to remember it again the next morning in order to graduate it. I find that 2hrs is a good step for this (so your Learning steps would be '1, 120'), but really anything longer than an hour and less than 12 would probably work.